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A Schiff base bearing two methyl substituents, namely, 6,6'-((1

The extraction of cellulose from almond shell powders was carried out using three different particle sizes (125 µm, 250 µm, and 500 µm) of the powders. The powder samples were subjected to Soxhlet ...

Oil palm empty fruit bunch (OPEFB) was heat treated at 180°C using a vacuum oven for one hour, extruded and compounded with high-density polyethylene at 10%, 20% and 30% weight fraction. The compos...

Oil-palm empty fruit bunch (EFB) is a waste matter that is abundantly generated from the oil palm industries. Natural fibers derived from this lignocellulosic biomass have the potential to be used as reinforcement material in polymer composites as a greener alternative to synthetic fibers. However, some treatment has to be done to overcome inherent disadvantages in natural fibers and further improve its properties. One such method to prepare the fibers for chemical modification is by alkalization. In this study the EFB fibers were immersed in sodium hydroxide (NaOH) solution with concentrations and immersion times varied to 4, 8 and 12 w/v % and 6, 12, 24 and 48 h, respectively. The EFB fibers were characterized using FTIR, TGA, XRD, FE-SEM, diameter profiling and mechanical tests. Results from FTIR showed that the treated EFB have significant increment of intensity at 3335 cm-1 corresponding to -OH groups. Optimum treatment conditions for the EFB fibers were found at 4 w/v% NaOH and 24 h. Diameter profiling showed better uniformity in the treated EFB fibers with improved tensile properties.

Nanocellulose is an emerging biopolymer which has seen wide applications in biomedical and materials engineering. This book chapter presents the advances of nanocellulose in electrochemical applications which begins with the structural characteristics, physicochemical properties and methods of extraction of nanocellulose from biomass. The electronic conductivity of nanocellulose composites with graphene, conducting polymers such as polyaniline and polypyrrole is reviewed, which has seen applications as supercapacitors in energy storage devices. The applications of nanocellulose as membranes in energy storage devices such as lithium ion batteries and solar cells, in addition as anti-corrosion additives in paint coatings and recently as modified electrodes for electrochemical sensing of biological compounds are presented and discussed.

The optical properties of a series of side chain liquid crystalline polymers (P1–P3) containing azo-benzothiazole mesogen with different terminal substituents (–H, –CH3 and –OCH2CH3) in four organic solvents of varying polarity have been investigated by absorption and fluorescence spectral analysis. Solvatochromic studies of P1–P3 did not show any regular variation on the absorption and emission intensities with changing the polarity of solvent. Theoretical studies were performed based on different solvent correlation methods such as Dimroth-Reichardt and Kamlet-Taft methods to investigate the solute-solvent interactions. Both absorption and emission maxima of investigated polymers were bathochromically shifted with the replacement of sixth position hydrogen atom by electron donating groups in benzothiazole moiety. The emission intensities of the studied polymers showed decreasing trend with increasing temperature.

Four azo-ester mesogens with lateral methyl were synthesized where these compounds are differed by the terminal substituents i.e. –H, –Cl, –Br and –CN. The compound with -H terminal substituent displayed nematic behavior with narrow mesophase range while electron-withdrawing groups terminated compounds exhibited mesophase behavior with wider nematic range. The presence of lateral methyl group and different terminal substituents used in this study could be utilized to generate anticipated mesophase. Their mesogenic behavior was also compared with previously investigated analogues and other structurally related series to evaluate the effect of lateral methyl group on the mesomorphism. Optical investigations demonstrated that their absorption spectra are identical in shape because of the structural similarities in the mesogenic unit whereas the fluorescence spectra exhibited blue emission and were red-shifted with the incorporation of terminal substituents. The synthesized azo-ester compounds could be potential candidate as fluorescent materials for practical applications such as organic light-emitting diode applications.

Acid surface modified carbon nanotube (MCNT)-, Carbon nanotube (CNT)-filled fluoroelastomer (FE) and unfilled-FE were prepared (MCNT/FE, CNT/FE and FE). The compounds were subjected to thermogravimetric analysis (TGA) and heat air aging, and characterized by Energy Dispersive X-Ray (EDX). Results showed that MCNT improved the thermal properties of FE, resulting in a larger amount of FE and char remaining in the temperature range of 400-900 °C relative to unfilled FE and CNT/FE. The MCNT/FE TGA curve shifted towards higher temperatures compared to CNT/FE and FE. The same results also revealed that higher percentages of FE were undegraded or less degraded especially near MCNT in the temperature range of 400-540 °C. Energy Dispersive X-Ray (EDX) results indicated that the percentage of carbon and fluorine in the residue of TGA scans, up to 560 °C, of MCNT/FE were the same as CNT/FE, and were higher than FE. EDX results of TGA residue (run up to 900 °C) showed that most of the undegraded FE, which was not degraded at temperatures below 560 °C, was degraded from 560 °C to 900 °C in both MCNT/FE and CNT/FE, with the char in MCNT/FE being more than that in CNT/FE. EDX analysis of thermal aged specimens under air showed that, with increasing aging time, a greater percentage of C, O and F was lost from the surface of filler/FE and FE. The order of element loss after 24 hour aging time was: MCNT/FE > FE > CNT/FE.